How to fix the thunderbird connection error with Gmail?

The Thunderbird connection error with Gmail means there is some problem with the antivirus working on the system therefore; first of all see to it that your software is well updated see to it that the software firewall is not blocking thunderbird program also see to it that the antivirus is not blocking the Google in the settings. If you are still not able to fix the error then for guidance ask at Thunderbird customer service number & http://www.emailsupportcontactnumber.co.uk/thunderbird-help.php